MAINTAINERS: renesas: Add "renesas," file contents pattern

Add a keyword match pattern for the word "renesas," in files to the
ARM/RISC-V/RENESAS ARCHITECTURE section.  This make sure patches
changing drivers that match against "renesas,<foo>" (as used mostly for
Renesas on-SoC components) are CCed to the linux-renesas-soc mailing
list.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/c1be1e97c5457eade25b0eb5118196677cecfc08.1679039809.git.geert+renesas@glider.be

Author: geertu

MAINTAINERS

@@ -2654,6 +2654,7 @@ F:	arch/arm64/boot/dts/renesas/
 F:	arch/riscv/boot/dts/renesas/
 F:	drivers/soc/renesas/
 F:	include/linux/soc/renesas/
+K:	\brenesas,
 
 ARM/RISCPC ARCHITECTURE
 M:	Russell King <linux@armlinux.org.uk>